As a background art of the technical field relating to the present invention, a fuel injection valve disclosed in Japanese Patent Provisional Publication No. 2003-336562 (Patent Document 1) is known. This fuel injection valve has a valve seat member; a transverse passage that communicates with a downstream end of the valve seat; and a swirl chamber in which a downstream end of the transverse passage opens in a tangential direction. Furthermore, the transverse passage and the swirl chamber are provided between the valve seat member and an injector plate coupled to a front end surface of the valve seat member. The injector plate has each of fuel injection orifices which jets fuel having gotten a swirl in the swirl chamber. In the fuel injection valve, the fuel injection orifice is offset by a predetermined distance from a center of the swirl chamber toward an upstream end side of the transverse passage (see abstract). With this structure, atomization of the injected fuel is promoted, and a fuel injection response is improved.
However, in the fuel injection valve for jetting a fuel wherein the transverse passage, the swirl chamber, and the fuel injection orifice are formed on the injector plate, generally a spray angle is set by adjusting a diameter and length of the fuel injection orifice and a size (diameter) of the swirl chamber. If any one of the diameter and length of the fuel injection orifice or the size (diameter) of the swirl chamber is changed in order to adjust the spry angle, an amount of fuel jetted from the fuel injection orifice (fuel injection amount) is changed. Therefore, a long times have been spent on determining the diameter and length of the fuel injection orifice and the size (diameter) of the swirl chamber so that both of the fuel injection amount and the spray angle are kept within the predetermined range.